[Setter Dog]

Hello Friends,...I'm back with another lens question.

I'm looking for an expensive 70-300mm lens for occasional use on my K3. I'm interested only in the quality of the lens at 300mm. There are plenty of Sigmas available at very good prices but they are described in various ways, DG, Macro, APO, etc. I can't find any information on what the differences are. The specs on all look exactly the same.

If anyone has a recommendation for which of the above Sigmas is best, I'd appreciate hearing from you.

Tamron makes a 70-300 also. Is it a better choice?

Thanks,...Jack

[wed7]

Yep, the tamron is sharp and contrasty

[boriscleto]

If you are looking for a lens to use at 300mm consider the DA L 55-300. These are usually available for less than $200 and are better at 300 than any of the Sigma or Tamrons.

[Des]

There are plenty of Sigmas available at very good prices but they are described in various ways, DG, Macro, APO, etc. I can't find any information on what the differences are. The specs on all look exactly the same.

Sigma's terms:
DG - lens designed for digital cameras. Has better coatings. Some Sigma lenses are designated "DG". What does this mean? | Sigma Corporation of America
Macro - Strictly this means lenses that can focus very close to the subject, so that the image produced on the sensor is the same size as the subject (1:1) or even greater. But the term is bandied around to describe various lenses that can take close focus photos. The current Sigma 70-300 (Sigma 70-300mm F4-5.6 APO DG Macro Lens Reviews - Sigma Lenses - Pentax Lens Review Database ) can produce images to a ratio of 1:2. That is very good for a zoom lens. Of course the image quality won't be nearly as good as from a dedicated macro lens (or, I suspect, from the Pentax 55-300 with a Raynox diopter - see below).
APO - Sigma says this: "Apochromatic lenses are telephoto and telezoom type lenses which use special optical designs and optical materials (SLD or ELD glass) to improve their performance. The result is images which have greater contrast, sharpness and color definition than a comparable non-APO type lens . All Sigma apochromatic lenses are identified by the APO designation in their descriptions."

Check the PF user reviews for the various models:
Sigma Lenses for Pentax: Current Zoom Lenses - Pentax Lens Review Database - current models
Sigma Lenses for Pentax: Legacy Zoom Lenses - Pentax Lens Review Database - legacy models

See here for the current model Tamron 70-300: https://www.pentaxforums.com/userreviews/sigma-lenses-for-pentax-zooms-c74.html

If you are looking for a lens to use at 300mm consider the DA L 55-300. These are usually available for less than $200 and are better at 300 than any of the Sigma or Tamrons.

+1. The Pentax 55-300 comes in 3 versions: DA-L, DA and DA WR. They are optically identical. Only the DA WR is available new.

The DA-L is one of the all time great lens bargains at around $US150 second-hand (DA version usually goes for about $50-70 more). The DA-L differs from the other two versions in that it has a plastic mount (not metal), doesn't come with a lens hood and doesn't have Quick Shift (manual focus override), but these limitations are minor. The plastic mount has proven quite durable. You can buy a lens hood for $5 on ebay. QuickShift is a nice feature (useful if you use back-button auto-focus), but not essential (the Sigma and Tamron xx-300mm lenses don't have it anyway).

If you would like to take macro or very close shots of flowers, insects and all manner of other small things without spending the extra on a specialist macro lens, the 55-300 pairs well with a Raynox 150 diopter (about $80: DCR-150 Macro conversion lens for D-SLR camera). The Raynox just attaches to the end of the lens. People have got great results with the Raynox: https://www.pentaxforums.com/forums/122-lens-clubs/74221-raynox-macro-club.html

The Pentax is sharp (for a consumer zoom), lightweight, compact, handles well and produces very good colours. Not particularly susceptible to chromatic aberrations (the Tamron is notorious for purple fringing). On the K-3, it will benefit from the faster AF drive. If you shoot jpg only, the camera can do in-body correction of distortion, vignetting etc (this only works with Pentax lenses).

---

Last edited by Des; 03-28-2015 at 05:15 PM.

[tibbitts]

Hello Friends,...I'm back with another lens question.

I'm looking for an expensive 70-300mm lens for occasional use on my K3. I'm interested only in the quality of the lens at 300mm. There are plenty of Sigmas available at very good prices but they are described in various ways, DG, Macro, APO, etc. I can't find any information on what the differences are. The specs on all look exactly the same.

If anyone has a recommendation for which of the above Sigmas is best, I'd appreciate hearing from you.

Tamron makes a 70-300 also. Is it a better choice?

Thanks,...Jack

I don't have experience with the Sigmas, but my guess is that none of the consumer xx-300s is going to be an outstanding performer at 300mm. Generally I think it's safe to think of xx-200 as the best range and then 200-300 as a bonus. Having had experience with the Pentax 55-300 and the Tamron 70-300, my opinion is that if you get a good copy of the 55-300 and an equally good copy of the 70-300, the Pentax will be a slightly better performer. Good luck with getting a good copy. This is a range where there aren't many good options for Pentax, short of possibly the 60-250 Pentax, while Canikon users can upgrade to the supposedly optically superior (vs. the other consumer solutions) newer 70-300mm Tamron. Obviously if you want 300mm only , there's the 300mm Pentax, but it's not cheap, nor as small/light as the 70-300s.

My much-criticized 100-300F outperforms my 55-300 at 300mm, and the 100-300 is the "bad" 5.6 version. But the 55-300 performs much, much better at 55-100mm. Likewise, the 55-300 seriously outperforms the Tamron at 55-70mm. The Tamron also outperforms the Pentax at 300mm, unless you're in a purple fringing situation, in which case your happiness with the results may depend on circumstances (color of the surrounding elements, and the intelligence of your PF-reduction software.) I might be tempted to drag out the old 100-300, although none of my options is very PF-resistant. I paid under $70 used, LN in box, for the 70-300 Tamron; it's been one of the best values I've gotten. However I do miss the focus clutch (and, to a much lesser degree, the non-rotating front filter mount) on the Pentax.

I don't have anything with the megapixels of the K3, and I'm guessing if I did, I might be less happy with any of the consumer alternatives after pressing that "1" key for the first time than I am with my 10-16mp bodies.

[SpecialK]

There are plenty of Sigmas available at very good prices but they are described in various ways, DG, Macro, APO, etc.
Tamron makes a 70-300 also.

Thanks,...Jack

The APO (apochromatic) is the best of the Sigmas. The Tamron has been called a PF monster (purple fringe).

Just about everyone comparing those lenses and the Pentax 55-300 put the Pentax at the top. My Sigma APO was about equal to the Pentax 50-200, and both went directly to the shelf after I got the 55-300.

Used ones are reasonably priced - but get hood if you get a DAL version.

[Setter Dog]

Sigma's terms:
DG - lens designed for digital cameras. Has better coatings. Some Sigma lenses are designated "DG". What does this mean? | Sigma Corporation of America
Macro - Strictly this means lenses that can focus very close to the subject, so that the image produced on the sensor is the same size as the subject (1:1) or even greater. But the term is bandied around to describe various lenses that can take close focus photos. The current Sigma 70-300 (Sigma 70-300mm F4-5.6 APO DG Macro Lens Reviews - Sigma Lenses - Pentax Lens Review Database ) can produce images to a ratio of 1:2. That is very good for a zoom lens. Of course the image quality won't be nearly as good as from a dedicated macro lens (or, I suspect, from the Pentax 55-300 with a Raynox diopter - see below).
APO - Sigma says this: "Apochromatic lenses are telephoto and telezoom type lenses which use special optical designs and optical materials (SLD or ELD glass) to improve their performance. The result is images which have greater contrast, sharpness and color definition than a comparable non-APO type lens . All Sigma apochromatic lenses are identified by the APO designation in their descriptions."

Check the PF user reviews for the various models:
Sigma Lenses for Pentax: Current Zoom Lenses - Pentax Lens Review Database - current models
Sigma Lenses for Pentax: Legacy Zoom Lenses - Pentax Lens Review Database - legacy models

See here for the current model Tamron 70-300: Sigma Lenses for Pentax: Legacy Zoom Lenses - Pentax Lens Review Database


+1. The Pentax 55-300 comes in 3 versions: DA-L, DA and DA WR. They are optically identical. Only the DA WR is available new.

The DA-L is one of the all time great lens bargains at around $US150 second-hand (DA version usually goes for about $50-70 more). The DA-L differs from the other two versions in that it has a plastic mount (not metal), doesn't come with a lens hood and doesn't have Quick Shift (manual focus override), but these limitations are minor. The plastic mount has proven quite durable. You can buy a lens hood for $5 on ebay. QuickShift is a nice feature (useful if you use back-button auto-focus), but not essential (the Sigma and Tamron xx-300mm lenses don't have it anyway).

If you would like to take macro or very close shots of flowers, insects and all manner of other small things without spending the extra on a specialist macro lens, the 55-300 pairs well with a Raynox 150 diopter (about $80: DCR-150 Macro conversion lens for D-SLR camera). The Raynox just attaches to the end of the lens. People have got great results with the Raynox: https://www.pentaxforums.com/forums/122-lens-clubs/74221-raynox-macro-club.html

The Pentax is sharp (for a consumer zoom), lightweight, compact, handles well and produces very good colours. Not particularly susceptible to chromatic aberrations (the Tamron is notorious for purple fringing). On the K-3, it will benefit from the faster AF drive. If you shoot jpg only, the camera can do in-body correction of distortion, vignetting etc (this only works with Pentax lenses).

Thanks, Des, for that thorough explanation. Very, very helpful.

Jack

---------- Post added 03-28-15 at 08:33 PM ----------

The APO (apochromatic) is the best of the Sigmas. The Tamron has been called a PF monster (purple fringe).

Just about everyone comparing those lenses and the Pentax 55-300 put the Pentax at the top. My Sigma APO was about equal to the Pentax 50-200, and both went directly to the shelf after I got the 55-300.

Used ones are reasonably priced - but get hood if you get a DAL version.

Thanks, Special K! I think I'll look for a Pentax 55-300mm. Very helpful advice.
Jack